The new treatment targets gut hormone GLP-1 but also mimics amylin, a hormone released by the pancreas that suppresses hunger.

Novo Nordisk's U.S.-listed shares are surging 9% Friday morning after the Danish drugmaker reported early stage results for its amycretin weight-loss drug.

Some outcomes, like reduced risk of cardiovascular disease and increased chance of nausea, were expected. But others took researchers by surprise.